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                                                                    EXHIBIT 10.5


                    AMENDMENT NO. 1 TO INVESTMENT AGREEMENT


     This Amendment No. 1 to Investment Agreement (the "Amendment No. 1") is
made and entered into effective as of the 6th day of November, 1998, between
Recovery Equity Investors, L.P., a Delaware limited partnership (the
"Investor"), and CMI Corporation, an Oklahoma corporation (the "Company").

     WHEREAS, effective as of August 19, 1991, the Investor and the Company
entered into that certain Investment Agreement (the "Investment Agreement")
pursuant to which, among other things, the Investor purchased from the Company
6,666,667 shares of the Company's Common Stock;

     WHEREAS, the parties desire to amend the Investment Agreement;

     NOW, THEREFORE, in consideration of the premises and the mutual promises
herein made, the parties agree as follows:

     1.   Capitalized terms used herein and not otherwise defined herein shall
have their respective meanings as set forth in the Investment Agreement.

     2.   Section 4.1 of the Investment Agreement is hereby amended to read in
its entirety as follows:

     "SECTION 4.1. Board Representation. From and after November 6, 1998,
                   --------------------
     the Investor shall be entitled to designate for election to the
     Company's Board of Directors one-half (1/2) of the total number of
     directors then constituting the entire Board, as such number of
     directors shall be fixed from time to time pursuant to resolution
     adopted by the Company's Board of Directors; provided, however, that
                                                  --------  -------
     if, after the date hereof, the Investor, its affiliates, limited
     partners and associates cease to beneficially own an aggregate of at
     least 1,700,000 shares of Voting Class A Common Stock, par value $0.10
     per share ("Class A Common Stock"), of the Company, the Investor
     thereafter shall be entitled to designate for election to the
     Company's Board of Directors only one-third (1/3) of the total number
     of directors then constituting the entire Board; and, provided,
                                                           --------
     further, that if the Investor, its affiliates, limited partners and
     -------
     associates cease to beneficially own an aggregate of at least
     1,000,000 shares of Class A Common Stock, the Investor thereafter
     shall be entitled to designate only one (1) person for election to the
     Company's Board of Directors (it being understood that such
     entitlement to designate one director shall terminate at such time as
     the Investor, its affiliates, limited partners and associates cease to
     beneficially own any shares of Class A Common Stock). Any person
     designated by the Investor for election to the Company's Board of
     Directors in accordance with the provisions of this Section 4.1 shall
     be included in the slate of nominees

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          recommended by such Board of Directors to the Company's
          shareholders for election as directors at each applicable annual
          meeting of the shareholders of the Company, and the Company shall
          use its best efforts to cause the election of each such person
          designated by the Investor. In the event that any designee of the
          Investor for election to the Company's Board of Directors
          pursuant to the foregoing provisions shall cease to serve as a
          director for any reason, the vacancy resulting therefrom shall be
          filled as soon as practicable with a person designated by the
          Investor. Provided that he continues to beneficially own (with
          his wife, children and grandchildren) at least 1,500,000 shares
          of Class A Common Stock, Bill Swisher shall be entitled to
          designate himself for election to the Company's Board of
          Directors. If so designated, Mr. Swisher shall be included in the
          slate of nominees recommended by the Board of Directors to the
          Company's shareholders for election as directors at each
          applicable annual meeting of the shareholders of the Company, and
          the Company shall use its best efforts to cause the election of
          Mr. Swisher. Mr. Swisher is specifically made a third party
          beneficiary of the two sentences immediately preceding this
          sentence. In the event that (i) at any time the designee(s) of
          the Investor are not elected to the Company's Board of Directors
          as provided herein, or (ii) the Department of Labor through
          formal or informal rules, regulations, or interpretations
          provides, or it is otherwise provided through governmental or
          court action, that such Board representation does not constitute
          the exercise of management rights of the kind necessary to allow
          the Investor to continue to qualify as a venture capital
          operating company under Department of Labor Regulation 2510.3-101
          promulgated under ERISA, then the Investor and the Company shall
          use their best efforts, upon the advice of counsel to the
          Investor, to ensure that the Investor has and is permitted to
          exercise the minimum amount of such management rights to continue
          to qualify as a venture capital operating company; provided,
                                                             --------
          however, that in no event shall the Investor be entitled under
          -------
          this Section 4.1 to designate for election to the Board of
          Directors a number of persons greater than that set forth in the
          first sentence of this Section 4.1. The number and type of
          securities which the Investor, its affiliates, limited partners
          and associates (or Bill Swisher, his wife, children and
          grandchildren, as the case may be) are required to beneficially
          own to be afforded the right to designate persons for election to
          the Company's Board of Directors shall be appropriately adjusted
          to reflect any stock split, reverse stock split, stock dividend,
          recapitalization or similar action. The parties acknowledge and
          agree that, for purposes of determining the number of shares of
          Class A Common Stock or other securities of the Company
          beneficially owned by the Investor's limited partners, only those
          shares distributed by the Investor to the limited partners shall
          be considered."

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     3.   The parties acknowledge and agree that, for purposes of Section 4.1,
Tom Engelsman shall be deemed to be a designee of the Investor.

     4.   Except as specifically provided herein, the terms and provisions of
the Investment Agreement shall remain unchanged and in full force and effect.
This Amendment No. 1 may be executed in any number of counterparts, all of which
taken together shall constitute one and the same amendatory instrument. This
Amendment No. 1 shall be governed by and construed in accordance with the
internal laws of the State of New York without regard to the principles of
conflicts of laws.

          IN WITNESS WHEREOF, the parties hereto have executed below.

                                       RECOVERY EQUITY INVESTORS, L.P., a
                                       Delaware limited partnership

                                   By: Recovery Equity Partners, L.P., its
                                       General Partner


                                   By: /s/ Joseph J. Finn-Egan
                                       -------------------------------------
                                       Joseph J. Finn-Egan, General Partner


                                   By: /s/ Jeffrey A. Lipkin
                                       -------------------------------------
                                       Jeffrey A. Lipkin, General Partner



                                       CMI CORPORATION, an Oklahoma corporati


                                   By: /s/ Bill Swisher
                                       -------------------------------------
                                       Bill Swisher, Chairman of the

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